Field of the Invention
The present invention relates to a method for analyzing L-tryptophan employing L-tryptophan oxidase suited to measuring the content of L-tryptophan by converting the L-tryptophan in a biological sample into a product permitting the quantification of L-tryptophan and detecting or quantifying the product.
Brief Description of the Related Art
The quantification of amino acid concentrations in biological samples such as blood can be effective for detecting various diseases. The development of such quantification methods is highly desirable from a medical treatment perspective. Enzymatic methods of quantifying amino acid concentrations afford great advantages over instrumental analysis in terms of speed, convenience, and the like. They are considered useful for the detection of various illnesses at the actual medical treatment site.
Known prior art relating to the enzymatic quantification of L-tryptophan includes methods employing (i) L-tryptophan monooxygenase (Emanuele, J. J., Heasley, C. J., and Fitzpatrick, P. F. (1995) Arch Biochem Biophys 316, 241-248 and Simonian, A. L., Rainina, E. I., Fitzpatrick, P. F., and Wild, J. R. (1997) Biosens Bioelectron 12, 363-371) and (ii) methods employing L-amino acid oxidase (Japanese Un-examined patent publication No. 2001-069974).